Roof construction



Patented Feb. 2l, 1939 PATENT OFFICE ROOF CONSTRUCTION Stephan Szeg, London, England Application May 10, 1937, Serial No. 141,665 In Germany June 4, 1936 4 Claims.

This invention relates to a roof construction of the kind comprising diagonally arrangedintersecting beams, and the invention consists in the provision of a beam grid the members of which are 5 cranked alternately upwards and dcwnwardsalong lines which are parallel to a boundary and which coincide with the intersection points of the diagonal beams.

The cranking may be done either with the same l angle along every other row of intersection points,

or it may be done with different angles of inclination at two out of every three rows of intersection points so as to form a northlight type of roof. The statical advantage of this arrange- 15 ment is that a considerable part of the loads will be carried to the supports by normal forces, a fact which greatly reduces the bending moments as compared with those in a plane grid. The practical advantage obtained consists in the elim- 20 inaticn of all internal supports and members projecting below the planes of the roof structure. These features result in a notable saving of material and a better utilization of the covered space.

25 The invention is illustrated diagrammatically in the accompanying drawing.

Fig. 1 of said drawing is a plan View of the roof according to one construction,

Fig. 2 is a corresponding side elevation,

30 Fig. 3 is a plan View of a modified form of the roof,

Fig. 4 is a longitudinal section on the line IV-IV of Fig. 3, and

Fig. 5 is a corresponding side View of the edge 35 girders.

The roof comprises a beam grid which is composed of diagonally arranged, intersecting beams a and which is cranked alternately upwards and downwards along beam intersection points situ- 40 ated on lines which are parallel to a boundary, so as to form, parallelly to the latter, ridges at b and valleys at c. 'I'he roof span is surrounded by edge girders d under which supports e are arranged wherever required.

45 In the arrangement shown in Figs. 1 and 2 the cranking is done regularly with the same angle (Cl. S- 1) of inclination at every other row of intersection points, and alternate rows f of intersection points will thus be located on straight beam portions.

Figs. 3 to 5 show an arrangement wherein the cranking is done at two out of every three rows 5 of intersection'points and with different angles of inclination so as to form a northlight type of roof. In this case each longer and less inclined slope will have a central row g of intersecting points on the straight beam portions. 10

The edge girder d may have alternative slopes as shown in Fig. 5.

I claim:

1. A roof structure comprising a grid of two series of oppositely inclined and intersecting beams each continuous between the boundaries of said grid and diagonal to at least o ne of said boundaries and rigidly connected together at their intersection points, said grid being cranked alternately upwards and downwards along some rows of intersection points parallel to at least one of said boundaries but remaining uncranked at other rows of intersection points located at regular intervals.

2. A roof structure as claimed in claim 1 where- 25 in the grid is cranked through the same angle at every second row of beam intersection points.

3. A roof structure as claimed in claim 1 wherein the grid is cranked through different angles at two out of every three consecutive rows of beam intersection points.

4. A roof structure comprising a grid composed of two series of intersecting and oppositely inclined continuous beams passing through the grid from boundary to boundary and arranged diagonally to at least one of said boundaries, said beam members being rigidly connected together at their intersection points, said grid being cranked alternately upwards and downwards along some rows of beam intersection points parallel to at least one of said boundaries but remaining uncranked at other rows of intersection points located at regular intervals, edge girders surrounding the roof span, and supports arranged under said girders.

STEPHAN szEG. 

